Glow lamp



Feb. 19, 1935. R M w L 1,991,479

GLOWLAMP Filed March 29, 1929 avwemtoz mcHARu M. WILLIAMS menad fres.19, 193.5

' Richard M. to Radio tion of Delaware oLow LAMP William, Bidgewood, N.Y., assignor of America, a corpora- Application mm; 29, me, Serial No.350,922 14 Claims. (01. 176-122) The present invention relates to glowlamps, and particularly to the glow lamps adapted and suited to use inconnection with facsimile and television systems working in conjunctionwith radio, wired radio, or

telegraph line transmitting v and receiving systems.

Particularly, the invention is'directedtq 310w lamps .of the type whichare known as-point v t Still other and ancillary objects of myindischarge lamps, in that the glow appears as a point source incontrast to lamps over which the glow appears over a relativelylargearea. V

In the prior art, so far as I am aware, one of the principledifilculties encountered inconnection with glow lamps of the generaltype to be hereinafter described has been the fact that the life of thelamp was relatively short, and, in many cases,- limited to such valuesas50 to hours of use. This difficulty has-beenprincipally due to thefact that the electrodes disintegrate whenpotentials are appliedthereto, and particularly refers to what has become known in the art asthe cathode spatter. This spatter action, produced by disintegration ofthe cathode member of glow lamps has, heretofore, been mostobjectionablein that the disintegrated particles seem to collect on theinside of the glass envelope or window which surrounds the electrodes ofthe lamp, and as this inner surface becomes blackened by the actionof'the collected disintegrated particles, it will eventually preventlight produced withinthe lamp from being projected outwardly through theglass envelope housing the electrodes.

It is therefore an object of my present inventionto develop a glow lampinwhich the life is increased to a very material extent.

Still a, further object of my invention is to produce a glow lamp inwhich any cathode spatter will in no way tendto block light from passingbeyond the electrodes and a lamp in which the spatter cannot cover theinner surface of the enclosing envelope or casing. v I

Still another object of my invention is to provide a glow lamp in whichmeans is provided for collecting the cathode spatter and thus prevent itfrom reaching the inner surface of the glass enclosing envelope.

Still another object of my invention is to pro-' vide a glow lamparrangement in which provision is made for producing better heatradiation and thus increase efficiency in the lamp by conducting theheat away from the cathode glow portion to the outside portions of thetube.

Still further objects of my invention are to provide a glow lampstructure of thetype to be hereinafter described, which is relativelysimple in its construction and arrangement of parts, a glow lamp whichis cheap and inexpensive to manufacture, one which can be easilyinstalled -in the now existing types of facsimile and televisionreceiving apparatus, and a glow lamp in which the emeiency of operationis increased to a material extent.

vention will at once become apparent and sus- 10 which the inventionrelates from a reading of the following specification in connection withthe accompanying drawing, wherein:

Fig. 1 illustrates a longitudinal sectional view through a glow lampconstruction of a preferred form; and,

Fig. 2 illustrates a sectional view taken on the line 2-2 of Fig. 1, inwhich the shield for preventing cathode spatter from blackening theingest themselves to those skilled in the art to ner sur face of theenvelope is more particularly shown.

Now referring more particularly to the drawing forming a part of thepresent disclosure, I have shown a glass enclosing envelope 1 as hous- 2ing the cathode and anode members of the glow lamp. This enclosingenvelope is of the same general type as the well known audions ortriodes well known in the radio art, and may be mounted upon the usualsupporting base provided with four prongs extending outwardly therefromfor the purpose of mounting in a socket in the same manner as the usualaudion, although for convenience of illustration and showing, thishasnot been specifically illustrated.

Extending inwardly from the mounting portion of the enclosing envelope1, I have supported a sealed-in stem member 3 for the purpose ofsupporting the electrodes of the lamp and forming therethrough aconnection with external circuits by means ofconnecting wires 5 and 7,which if desired, may be connected with two of the terminals of the fourprong base, generally known as the UK base of vacuum tube amplifiers. Inthis type of construction, the remaining two prongs will serve as blankcontacts and function merely as an additional mounting means. Thecathode member 9 of the glow lamp structure is preferably formed from asolid metal ring or cylinder, whose cross-sectional shape is preferablythat which is shown in the above illustration, and consists in a recessportion 11 extending inwardly from the lower portion thereof for apredetermined distance, with a small cylindrical opening -13 extendingthrough the center thereof from the outer portion thereof inwardly tothe recess portion 11. The entire cathode structure is then supportedwithin the enclosing envelope 1 by means of supporting members or feet15 and 1'7, with the supporting element 17, for example, connected withthe external circuit connection 5. So as to form a rigid supportingelement 15 or 17 for the cathode member of the glow lamp, it ispreferable to provide a sort of rigid wire mounting which is sealed intothe supporting foot 3. Such wire should in its nature be a metal whichforms a good electrical conductor, and, for this purpose, I have,therefore, preferably formed the supporting elements 15 and 17 fromnickel wire, due to its inherently good conducting properties and itsunusual strength, although it is to be understood that other types ofwire, such as tungsten, copper, or molybdenum, might be substitutedwhere desired.

Also supported from the supporting stem 3, and preferably formed as apart thereof by fusing the same, I have provided a glass sleeve member19 extending into the recess portion 11 of the cathode structure, andwithin the enclosing sleeve 19, I have mounted the anode member 21,forming the second electrode of the glow lamp. The

anode member, similarly to the supporting elements 15 and 17 for. thecathode structure 9, is also rigidly mounted in the supporting stem 3,and is likewise preferably formed from a nickel wire, and connected bymeans of the conductor '7 to one of the four prongs of the base mounting(not shown).

Upon the upper portion of the cathode member, I have provided a ringlike projection 23 extending about the circumference thereof, and withinthis ring like portion, I have placed a circular piece of insulatingmaterial 25, such as a mica washer, for example, which is provided atits central portion with an opening 27 through which the glow discharge,produced by the cooperative action of the cathode and anode with anapplication of potential thereto, may be seen. For the purpose ofsecurely fastening the mica strip 25 to the cathode structure 9, I havecrimped the portions 29 which serve to rigidly secure the mica washer tothe cathode structure.

To describe now the operation of the glow lamp when potentials aresupplied thereto through the conductors 5 and 7, it will appear thatthere will be a glow taking place between the cathode structure 9 andthe anode structure 21. Since the anode is arranged at the center of thetube and along the axis thereof, and since ionization occurs between thecathode and anode, all of the glow produced will be concentrated withinthe space 13 formed by the cylindrical opening through the cathodemember, and the glow therein produced may be observed by looking at thetube along the axis thereof in a direction as shown by the arrow onFig. 1. In order that there may be no conduction between the anode andcathode leads 17 and 21 in the lower portion of the cathode member, andalso in order that there may be no glow produced in this portion wherethe cathode member 9 is recessed at 11, I have arranged the glass sleeve19 which will concentrate all of the glow within the cylindrical opening13 as above described.

To describe now further properties of the glow lamp by which the windowportion of the enclosing envelope 1 may be shielded from the spatter ordisintegration of the cathode member 9, which will commence at the edges31 thereof,

it will be recognized that if potentials are applied to the anode andcathode members 21 and 9 respectively, the space portion 13 and exteriorregion adjacent to opening 27 will become ionized and positivelycharged. This will cause the mica or other insulating surface 25 toassume a positive charge, since it is'located-within a positive region.It is well known in the art that the spatter particles are negative, andas these spatter particles fly through the hollow cathode portion 13,they may pass through the opening 27 in the mica. However, due to thepositive charge on the mica surface, which is opposite to the chargeexistent on each particle, the particles are defiected and,consequently, concentrated about the mica washer beginning at a pointimmediately adjacent the opening 27 and produce a blackening thereon. Asthe lamp is used more and more, the blackening action produced graduallyspreads out from the center of the mica washer 25 until it extendssubstantially over the entire area. Thus, it will be apparent that therate of blackening of the window of the enclosing envelope will begreatly decreased and the useful life of the lamp accordingly increased.

With further reference to the structure of the cathode member 9, it willbe observed that this is formed from a hollow cylindrical block, whichmay preferably be, of aluminum, although nickel, or iron, or othermetals may be substituted where desired. However, most satisfactoryoperation has been found to be produced by the use of aluminum due tothe low cathode voltage drop, the low spattering properties, thelightness in weight thereof, which tends to reduce the size of thesupporting elements therefor, and the fact that aluminum is an unusuallygood conductor of heat.

Also, in view of the fact that the cathode member is formed from ahollow cylindrical block, better heat radiation is accomplished, and thetem peratures within the lamp during periods of glow therein areconsiderably reduced because of the fact that the aluminum serves toconduct the heat away from the cathode glow portion to the outerportions of the tube, where a relatively large radiating surface isprovided.

It is also well known in the art that various inert gases are muchpreferred to the chemically active gases such as hydrogen, nitrogen, forexample, although either of these gases might be used and still producean operative arrangement. However, due to the fact that a gas of achemically active nature seems to eventually disappear, the use of suchgases has not been found to be espe cially practical. In the case of theinert gases, when using neon gas, for example, the light produced fromthe glow has been found to consist principally of red light with smallportions of yellow and green mixed therewith; when using argon, forexample, the light produced has been found to be distributed more evenlyover the entire visible spectrum and to be much richer in theultraviolet; and, when using helium gas, for example, the light producedby the glow action will consist of the red, the yellow, and the violet,although to the eye the glow appears rather yellowish.

By experimentation, it has been observed that argon gas within theenclosing envelope produces most satisfactory results due to its lowionizing potential and actinic light produced. Helium gives a veryactinic light but is not used because of its high ionization potential.

It is also possible to utilize a mixture of the above named inert gasesto produce satisfactory glow results. Or, if a trace of mercury is usedin conjunction with the various inert gases which fill the lamp, theactinic value of the light is greatly cathode and anode during periodswhen potentials are applied thereto, in case there is a relatively largeopening, for example of an inch, and sufficiently high gas'pressure, thelight, due to the cathode glow, that wouldv appear would seem to be aring of light, but with mercury used jointly with the various inertgases especially argon a bright or intense core of light appearsalongthe axis of 13. This core emits the mercury arc spectrum which is richin ultraviolet light.

In conjunction .with the use of mercury and the other inert gases,'themercury spectrum will be present at the expense of the inert gasspectrum. That is, the mercury atoms receive their energy directly byimpacts with positive'ions and hence the greater the average kineticenergy of the positive ions, the more strongly will the mercury spectrumappear.

In addition to what has been above described,

certain modifications and changes will at once suggest themselves tothose skilled in the art to which the invention relates, and I thereforebelieve myself to be entitled to make all of such changes andmodifications which fall fairly with-,

in the spirit and scope of the present invention as defined by thehereinafter appended claims.

Having now described my invention, what I claim and desire to secure byLetters Patent is the following:

l.' A glow lamp structure having a cylindrical cathode member, an anodemember supported.

within said cathode member, means for insulating the anode and cathodemembers with respect to each other for a space substantiallycorresponding to the distance which the said anode extends within thecathode, and an enclosing envelope surrounding each of said members.

2. A glow lamp structure having a hollow cylindrical cathode member, ananode member'mounted in the hollow portion of said cathode member, aninsulator extending within the hollow portion of the cathode for adistance substantially corresponding to the distance which said cathodeextends therein for rendering the said portion of the cathode inactive,and an enclosing envelope surrounding both of said members.

3. A glow lamp structure having a cylindrical cathode member providedwith a hollow portion extending through the central portion thereof, ananode member extending within an inactive portion of said hollow cathodemember, and an enclosing envelope surroundingboth of said members.

4. A glow lamp structure having a cylindrical cathode member providedwith a hollow portion extending through the central portion thereof,shielding means within oneend portion of the cathode, an anode membersupported within the hollow portion of said cathode member and ex--,.tending therein over an inactive portion, an en- ;velope.

5. In a 'glow lamp construction, a solid cylindrical cathode memberhaving a central opening therethrough, an anode member positioned alongtheaxis of said cylindrical cathode member and extending into aninactive portion of the cathode and an enclosing envelope for both ofsaid anode and cathode members.

6. In a glow lamp construction, a solid cylindrical cathode memberhaving a central opening extending longitudinally thereof, an anodemember positioned within said cylindrical opening and along a portion ofthe axis thereof, an insulating member between said anode and cathodeextending inwardly-of said cathode structure over a distancesubstantially. corresponding to the extension of said anode memberwithin said cathode, and an enclosing envelope surrounding both saidcathodeand anode structures.

'1. In a'glow lamp construction, a cylindrical cathode member having acentral opening therethrough, an anodemember positioned along the axisof said cylindrical opening in said cathode member and extending for asmall distance within an inactive portion of said cathode member,whereby the glow produced by the application of electrical potentials tosaid cathode and anode members is concentrated within the cylindricalopening through said cathode member, and an enclosing envelopesurrounding both said anode and cathode members.

8. In a glow lamp construction, a solid cylin-' drical cathode memberhaving a central opening extending longitudinally therethrough, saidopening being enlargedat one end thereof, an anode member positionedwithin said enlarged portion of the opening in said cathode member andalong the axis thereof and extending within said cathode member for aportion thereof substantially corresponding to the enlargement of saidreceased portion, an insulating member extending within said enlargedrecessed portion of said cathode for shielding the said cathode andanode one from the other and concentrating the glow discharge producedby the application of electrical potentials to said cathode andanodewithin the cylindrical recessed portion of said cathode,

and an enclosing envelope surrounding said cathode and anode structures.

9. In a glow lamp construction, a solid cylindrical cathode memberhaving a longitudinal opening extending therethrough, an anode memberextending within the lower portion of said cathode member along thelongitudinal axis thereof for a predetermined distance, a layer ofinsulating material supported upon the upper portion of said cylindricalcathode member for concentrating the entire glow discharge produced bythe application of electrical potentials to said cathode and anodewithin the said hollow cylindrical portion thereof and for collectingspattered particles produced by the disintegration of said cathodemember during periods of glow discharge, and an enclosing envelope sur-4 rounding said cathode and anode structures.

10." 'In a glow discharge lamp, a solid cylindrical cathode memberhaving a longitudinally extending central opening therethrough, saidopening being enlarged at one end thereof, a ring of insulating materialextending about the inner surface, of said enlarged portion of saidcathode opening for rendering the enlarged portion of cathode member forconcentrating the entire glow discharge produced by the application ofelectrical potentials to said cathode and anode members within the saidlongitudinally extending cylindrical portion of said cathode, meansprovided by said insulating ring for collecting spattered particlesproduced by cathode disintegration, and an enclosing envelopesurrounding said cathode and anode members.

11. In a glow lamp construction, a solid cylindrical cathode memberhaving a longitudinal opening extending through the central portionthereof, an anode member extending inwardly of said cathode member for apredetermined distance through said longitudinal opening therein, meansfor shielding said anode and cathode structures with respect to eachother over a distance corresponding to the extension of said anodemember within said cathode, a layer of insulating material supported bysaid cathode anode structure for concentrating the entire glow dischargewithin the cylindrical portion of said cathode member and for collectingspattered particles produced by cathode disintegration during periods ofglow discharge produced by the application of electrical potentials ofsaid cathode and anode members, and an enclosing envelope housing saidcathode and anode structures.

12. In a glow lamp, 9. solid cylindrical cathode having a centralopening therethrough, a punctiform anode located axially of saidopening, nonconducting means supported by the cathode to restrict thearea of glow discharge within the cathode opening, and an enclosingenvelope closely adjacent said cathode and surrounding both of saidelectrodes.

13. Electrodes for vacuum tubes comprising an elongated conductor openat both ends, and a conductor extending partially into said firstconductor from an end thereof, and means for restricting electrodeaction to the interior of said elongated conductor.

14. A light producing unit comprising a glass envelope, a tube-likeelectrode therein and another electrode having a portion extending intostructure along the surface thereof opposite said an end of said firstelectrode a distance less than the length of said first electrode, saidelectrodes being spaced with respect to said envelope in a mannerpreventing light producing action at the exterior portions of saidelectrodes.

RICHARD M. WILLIAMS.

